Building Geometry as a Variable in Energy, Comfort, and Environmental Design Optimization—A Review from the Perspective of Architects

Due to negative environmental impacts caused by the building industry, sustainable buildings have recently become one of the most investigated fields in research. As the design technique itself is mainly responsible for building performance, building energy design optimization is of particular interest. Several studies concentrate on systems, operation, and control optimization, complemented by passive strategies, specifically related to the envelope. In building physics, different architectural considerations, in particular, the building’s shape, are essential variables, as they greatly influence the performance of a building. Most scientific work that takes into consideration building geometry explores spaces without any energy optimization or calculates optimization processes of a few basic variables of simplified space geometries. Review studies mainly discuss the historic development of optimization algorithms, building domains, and the algorithm-system and software framework performance with coupling issues. By providing a systemized clustering of different levels of shape integration intensities, space creation principals, and algorithms, this review explores the current status of sustainability related shape optimization. The review proves that geometry design variable modifications and, specifically, shape generation techniques offer promising optimization potential; however, the findings also indicate that building shape optimization is still in its infancy.

Tomotok: python package for tomography of tokamak plasma radiation

A python package, called Tomotok, focused on performing tomographic inversion of tokamak plasma radiation is being developed at the Institute of Plasma Physics of the Czech Academy of Sciences. It aims at providing multiple inversion algorithms with an user friendly interface. In order to enable and ease performing tomographic inversion on different devices worldwide, it is planned to publish this software as open source in the near future. In this contribution, the package structure allowing an easy implementation of various tokamak and diagnostic geometries is described and an overview of the package contents is given. Apart from inversion methods, overview of Tomotok auxiliary content is given. The package provides tools for creating simple synthetic diagnostic system. These can be used for testing and benchmarking the code. This includes tools for building geometry matrices that describe the view of detectors using single line of sight approximation and artificial data generators capable of creating simple or hollow Gaussian profiles. The implemented inversion methods cover the minimum Fisher regularisation, biorthogonal decomposition and linear algebraic methods. The implementation of each method is explained, example results obtained by inverting phantom models are presented and discussed. The computation speed of implemented algorithms is benchmarked and compared.

Exposure to Particles and Gases in a Shopping Mall: Spatial Heterogeneity and Outdoor Infiltration

Shopping malls in Hong Kong are usually located near major roads. Indoor air quality (IAQ) in these buildings is subject to infiltration of outdoor traffic-related pollutants, such as PM10, PM2.5, CO, and NO2. Furthermore, the existence of indoor sources and building geometry added to the complexity of variations in IAQ. To understand outdoor infiltration and spatial heterogeneity of these pollutants, we conducted fixed and cruise indoor sampling, together with simultaneous outdoor measurements, in a typical mall in Hong Kong. The cruise sampling was conducted indoors on a predesigned route and repeated 15 times. Outdoor infiltration was quantified based on regression analysis between indoor and outdoor sampling. Results showed that 75% of PM2.5, 53% of PM10, and 59% of NO2 were infiltrated into the mall during opening hours. Elevated PM2.5 and CO were observed during the dinner period, suggesting an impact from cooking. Substantial spatial variations were observed for PM10, PM2.5, and NO2, particularly at locations near entrances and restaurants. Measures are needed to reduce pollution intrusion from building openings and cooking-related sources to improve air quality in the selected mall. Fixed and cruise sampling methods used in this study provide insights on sensor deployment for future air quality monitoring in buildings.

Passive design of buildings: A review of configuration features for natural ventilation and daylighting

Passive design involves the utilization of natural forces such as natural ventilation and daylighting without mechanical input of energy, and is a subset of environmentally sustainable design (ESD), which offers solutions for more environmentally friendly buildings. This review is based on the premise that ESD interventions have an inherent cost on building projects. The aim is to review existing research on applications of various building configurations for facilitating the economical application of passive design, in terms of natural ventilation and daylighting. A systematic review of existing research during the previous decade (2010 – 2020) was conducted. In our findings, we compare and categorise concepts within building configuration in terms of their applicability to natural ventilation and daylighting. Our review identified seven categories of building configuration ie. building geometry, interior, context, envelope, fenestration, building plan and voids, with their associated parameters. It was discovered that building fenestration was the most frequently researched followed by building voids. The identified parameters point to the variety, diversity and trends of research in the field. The knowledge can be used in familiarising, assessing and evaluating various aspects of passive design of building configuration towards energy saving and ESD.

Simulation Methodology Based on Wind and Thermal Performance for Early Building Optimization Design in Taiwan

In a subtropical climate like that of Taiwan, the high temperature and humid environmental conditions often result in discomfort and health effects for building occupants. With regard to building geometry, the wind environment and thermal comfort assessment, which can enhance energy efficiency and the comfort and health of occupants, both ought to be considered as soon as possible in the design process. In view of the limited comprehensive design evaluation methods and design workflows regarding wind and thermal performance currently available, this research aims to develop an early decision support workflow that includes suggested performance evaluation methods and design optimization processes. The results of our case study show that the building had clear performance results using the proposed evaluation methods, making it easier for architects to understand and compare alternatives. Appropriate analysis and visualization of the results also effectively assisted architects in determining design solutions and making relevant decisions. The methods and results in this article can facilitate performance-based buildings for healthy and energy-efficient built environments.

Effect of a Powder Mould in the Post-Process Thermal Treatment of ABS Parts Manufactured with FDM Technology

The post-process thermal treatment of thermoplastics improves their mechanical properties, but causes deformations in parts, making them unusable. This work proposes a powder mould to prevent dimensional part deformation and studies the influence of line building direction in part deformations in a post-process thermal treatment of 3D printed polymers. Two sets of ABS (acrylonitrile butadiene styrene) test samples manufactured by fused deposition modelling (FDM) in six different raster directions have been treated and evaluated. One set has been packed with a ceramic powder mould during thermal treatment to evaluate deformations and mould effectiveness. Thermogravimetric tests have been carried out on ABS samples, concluding that the thermal treatment of the samples does not cause degradations in the polymeric material. An analysis of variance (ANOVA) was performed to study internal building geometry and mould influence on part deformation after the thermal treatment. It can be concluded that powder mould considerably reduces dimensional deformations during the thermal treatment process, with length being the most affected dimension for deformation. Attending to the length, mould effectiveness is greater than 80% in comparison to non-usage of moulding, reaching 90% when the building lines are in the same direction as the main part.

Mitigating urban heat island effect through integrated climate-sensitive planning framework: a study based in Singapore

<p><strong>Background</strong></p><p>Urban heat island (UHI) is known as one of the severe environmental problems, and thus, research on UHI mitigation from the perspective of urban morphology is indispensable, especially in tropical regions like Singapore.</p><p><strong>Objectives</strong></p><p>While studies were carried out to evaluate and relieve UHI effect in urban areas, research that conducted through integrated assessment of urban aerodynamic and long wave radiation is limited. This research aims to provide an integrated climate-sensitive planning framework to UHI mitigation by understanding urban morphology.</p><p><strong>Methods</strong></p><p>A district-scale case study in Paya Lebar Air Base (PLAB) was conducted to illustrate how the urban morphological study contributes to the initial planning by an integrated analysis of climate information. Two urban morphological indices, frontal area density (FAD) and sky view factor (SVF), were calculated to depict aerodynamic and long wave radiation, i.e., pedestrian-level wind speed and air temperature, respectively.</p><p><strong>Results</strong></p><p>The SVF modelling results indicate that the UHI intensity at surrounding areas could be 2℃ to 3℃. With future development, there is a potential risk to create a spreading and more intensive UHI. Aiming at this problem, the FAD map indicates the importance of linking open spaces to create air paths, while the ΔT map implies the necessity of separating building clusters with intensive UHI. Integrated planning strategies are then developed based on the balance between link and separation, focusing on site layout and building geometry. For site layout, open spaces, e.g., major roads, building setbacks, low-rise built areas, and green corridor, should be linked to form the potential breezeways. At the same time, buffer zones like secondary forest should be arranged between site and surrounding areas to prevent new and existing UHI clusters from merging together. As for the building geometry, as the important design parameters, building height, footprint area, and building height to width ratio (H/W) should be carefully decided. Accordingly, a multi-step workflow is developed as an integrated climate-sensitive planning framework.</p><p><strong>Conclusions</strong></p><p>Urban morphology makes an important contribution to UHI effect. Integrated UHI mitigations can be developed by balancing the strategies for spatial link and separation in urban planning and design, based on climate information, e.g., aerodynamics and heat. The integrated climate-sensitive planning framework is generally applicable to tropical regions with cooling needs, as the key is to minimize temperature rise due to long wave radiation while introduce cool air to the site.</p>

Aerodynamic optimization of building augmented wind turbines

The omnipresence of wind, low production cost and much advancement within the field, wind power provides a vast and promising renewable energy resource. With the current high prices of oil and pressure to reduce carbon emissions, wind energy has achieved great interest creating high demands for innovative wind technology. Additionally, producing energy at the door step of consumers, such as at consumer dwellings in urban areas, wind power provides a means of producing efficient and reliable energy. The use of architectural structures to provide an augmentation source for the wind has been pursued by some ambitious architects but the effects of building augmentation are still uncertain. This study used computational fluid dynamic models to analyze varying building geometries and their effects on power augmentation. A porous region was used to model a wind turbine back pressure across the gap between the buildings. Results show augmentation increases power production one to two times compared to equivalent size free-standing wind turbines. Results also show that certain wind incidence angles provide the best augmentation indicating that building geometry is optimal when design takes into consideration winds regularity azimuth.